Die machine for progressive sheet metal forming



Aug. 13, 1946. M N 2,405,738

DIE MACHINE FOR PROGRESSIVE SHEET METAL FORMING Filed OQt. 28, 1942Sheets-Sheet l A M w w NV 0 w v Q 1. mm M o I J ll 9 2 F O l 1 III. M#1-. VH4 I O O Aug. 13, 1946.

v. DETTMAN DIE MACHINE FOR PROGRESSIVE SHEET METAL FORMING 4sheets-sheet 3 Filed Oct. 28, 1942 INVENTOR HAROLD V.DETTMAN AT TORNEYSDIE MACHINE FOR PROIGRESS-IVEYSHEET METAL FORMING Filed oct. 28, 1942NTOR HVYEbiE-TTMAN 2,405,738

4 Sheets-sheaf Patented Aug. 13,1946

DIE MACHINE FOR PROGRESSIVE SHEET METAL FORMING.

Harold v. Dettman, Riverside, 111. Application October 28, 1942, SerialNo.463,586

My invention has for its object to provide a simple, economical andeffective machine for folding sheet metal or the edges of sheet metalplates, whereby the same may be utilized for interlocking seam unitsbetween the plates.

Another object of my invention is to provide a machine havingreciprocative jaws carrying male and female articulated dies, whereby afold or seam element is progressively developed through a series ofbiting or stamping movements of the jaws, combined with a relativemovement between the sheet to be stamped and said machine, whereby thesuccessive steps to complete the seam element are effected.

Another important object of my invention is to provide the die carryingstamping jaws with eccentric power means, whereby the jaws willprogressively form a seam element on the edge of a sheet and provide arelative feed movement, between the jaws and sheet following eachstamping movement.

A further object of my invention is to provide eccentric actuating meansfOr the stamping jaws, whereby said eccentrics will impart a combinedstamping and feeding movement for the sheet metal Worked upon.

A further object of my invention is to provide the relativereciprocative jaws with a lineal die for each jaw of the male and femaletype, wherein the lineal dies are gradually formed in a plurality ofchanging contours from the initial Or first die unit, to the completingor last die unit, whereby the sheet of metal, a it travels between thedies in a succession of stamping movements, will progressively completethe seam element.

With the above and other minor objects in view, the invention consistsin certain peculiarities of construction and combination of parts aswill be fully set forth hereinafter with reference to the accompanyingdrawings and subsequently claimed.

In the drawings:

Figure 1 represents a sectional elevation of a forming machine embodyingthe features of my invention.

Figure 2 is a plan view of the same with parts broken away and insection.

Figure 3 is a sectional end view of said machine, the section beingindicated by line 3-3 of Figure 1.

Figure 4 is a side elevation with parts in section illustrating amodified form of machine for folding the edges of sheet metal.

Figure 5 is another modified form of the machinewherein independentmeans is utilized for 2 Claims. (01. 153-41) die step to its final thestamping movement of the jaws and for feeding the metal sheet in step bystep time movemen Figure 6 is a still furthermodified form of my formingmachine wherein companion pairs of cranks impart reciprocative movementto the jaws followed by a horizontal feed movement of said aws.

Figure "7 same.

FiguresB to 13 inclusive illustrate modified sectional views of the seamforming dies wherein the metal is shown progressively from itsinitialdie forming step.

Figure 14 is a sectional view through a completed double seam betweensheets of metal which may be formed by my apparatus. I

Figure 15 i a sectional view of another possible form of seam whereintheinterlocking edges are simply in U form.

Figure 16 is another sectional view of a possible seam wherein the sheetmetal plates are positioned at right angles to each other and locked bya seam.

is a fragmentary plan view of the Figure 17 is a diagrammatic view of amodified form of fold or crimp at the edge of a sheet metal plate.

Figure 18 is a plan View of the same.

Figure 19 is a diagrammatic modified form of my invention wherein asheet of metal curved or in drum formation may be provided, with edgeseams in accordance with my invention.

Referring by characters to the drawings i and 2 represent upper andlower companion drive shafts geared to a power shaft 3 whereby thecompanion shafts are rotated in synchrony. The drive shafts are mountedin a suitable frame and a best shown in Figures 1 and 2 they terminatewith eccentric ends 4-4 and 5-5 respectively. Mounted upon the companioneccentrics is an upper die bed 6 and a lower die bed i which die bedscarry a series of male and female dies 8 and 9 progressively developinga seam element from the first die to the finishing die in the series.The frame, as shown, may be provided witha table 8' for the support of asheet of metal A, the edges of which are adapted to be folded to effeeta eam element as said edges pass through the stamping machine.

As indicated in Figure 3 of the drawings, the metal sheet A may in someinstances be guided top and bottom by rollers B extending from the frameof the machine. I

The above described simple exemplification of my machine will operate asfollows and may be best understood by referring to the diagrammaticviews Figures 8 to 13.

The thin metal sheet is first fed under the initial die element instraight form at the time when the eccentrics have opened up the diebeds, as the eccentrics close the die beds, a short section of the sheetedge will be stamped with slight offsets which are primary and initiallyintended to form a seam and hence as the die beds are rapidly rotated bythe eccentrics in the direction of the arrows, this vibratory movementcauses a sheet of metal to be fed forward slightly at the point ofbiting of the dies and when the dies are opened they will vibratebackwardly and take another bite of the material and so forth until thecomplete fold is affected, by the movable series of progressive male andfemale dies as shown in the Figures 8 to 13 referred to.

In these diagrams the fold is shown, as what might be termed a doublelock seam, and when completed the other sheet seam element, will beinterlocked as shown in Figure 14. In other words, the interlocked sheetmay be a seam wherein two sheets of metal are secured upon a fiat planeor one of the sheets maybe at a right angle to its companion sheet.Referring to Figures 15 and 16 of the drawings a single seam is showncompleted, which can be readily formed by providing the proper movabledie bed.

Figures 17 and sheet of metal subjected to dies to produce a corrugatededge, it being understood that these progressive dies may be formed in asingle sheet or in blocks suitably attachedto the die beds.

While I have shown and described th sheets and dies arranged to bemounted in fiat formation, it is understood that the edges of suchsheets may be curved or in cylindrical form in place of the flat, inwhich case the die beds and dies would be curved to conform to the drummetal operated upon as indicated in Figure 19.

From the foregoing description it will be noted that the slighteccentrics are to be driven at a very high speed and the same will causea rapid vibration in a forward direction to feed the material and saidfeeding stroke is quite short, hence the progressive die formation, fromend to end of the series, would increase in a flowing manner orprogressively corresponding to the short feed distance of the dies.

In some instances it may be desirable to increase the speed of theseaming operation and this can be done by increasing the distance of thefeed of the sheet between each die stamping operation, illustrates upperand lower die beds l and H.

The lower die bed I I is reciprocatively mounted upon guide rollers l2extending from the frame and said bed is provided with dowels l3 whichextend through apertures in the upper die bed l0 whereby said companionsets of beds are reciprocated in unison. The upper die bed H) is formedwith ears l4 having cam tracks l5 therein, adapted to be engaged byrollers l6 carried by rotating cranks H, which are formed at the end ofthedrive shafts l-l, which shafts are actuated by any means forimparting timed rotation there to.

From the foregoing description with reference to Figure tween the diesthe initial formation of the seam will be of greater length or of thesame length as the initial die bite. Hence, when the cranks are in theposition shown in Figure 4, the die beds have been fed to their extremeposition rear- 18 show a modified form of a for example Figure '4' ofthe drawings 4, when the sheet of metal is fed bewardly and upon thenext quarter of the revolution of the cranks said die beds will becaused to articulate and form the first step in the seam. The nextquarter of the revolution of the cranks will cause the beds, in theirbiting union to move and feed the sheet forward the length of the dieoperation, th next quarter movement of the cranks will cause the upperdie beds to lift and disengage the metal worked upon and upon suchdisengagement, the cranks I! will complete the cycle by a rearwardreciprocative final movement, for the next bite of the sheet metal edge.

The above exemplification of my invention i1- lustrates simply anotherform of utilizing the bite between the male and female die members forfeeding the sheet, step by step to be seamed.

Referring now to Figure 5 of the drawings a still further modified formof my invention is exemplified, wherein I employ one cam controlledmeans for causing the bite or stamping action between the mold membersand an independent means for feeding the sheet of metal step by step asit is worked upon by the reciprocative mold. In this instance, the upperpair of drive shafts l-| have mounted thereon armed eccentrics 18connected by a link l9. A roller extending from the front end of thelink 19, engages a double track cam 20 suitably mounted upon the driveshaft 2| revolvable in bearing with which the frame is provided. Theupper bed 22, carrying the die formations is held in its open positionby counter balance springs 23 engaging guide dowels 24 which serve tohold the die bed in a vertical reciprocative action, The lower die bed25 is fixed and may constitut part of the machine frame. I

The sheet of metal A in this instance is fed between upper and lowergripping jaws 26, linked to an oscillating lever 21, The lower end ofthe lever 21 is connected to a similar lever 28 pivoted at the oppositeend of the machine frame and the upper end of this last mentioned leverhas a roller 29 which also engages the double cam track 20. When theparts are in the position shown in Figure 5, upon further, rotation ofthe cam wheel the sheet feed mechanism will move the sheet A one stepforward followed by a die stamping operation through movement of thelever cams l8, caused by outward travel of the roller l9 carried by thelink i9 to the outer surface of said cam wheel 20. Hence, we havedemonstrated that means may be provided for independently feeding thesheet of metal to be worked upon, It will also be apparent that I mayutilize stripper fingers X, which will extend through the lower bed, andare carried by the reciprocative upper bed 22, whereby the sheet ofmetal after each forming operation may be positively stripped from thebite between the male and female dies.

Referring to Figure 6 of the drawings, I have illustrated a mechanismsimilar to that shown in the upper reciprocative die bed in Figure 4 ofthe drawings. In this form of my invention I provide a reciprocativelower die bed H with companion cams 15' similar to the upper cams in allrespects. In this exemplification of the invention, with thesynchronized crank shafts put into operation, the dies will first bebrought together for stamping, followed by a forward feed movementfor'the sheet during the biting action of the dies. When the forwardfeed movement is completed the cams will cause the'dies to openvertically, whereby the metal is freed from the bite and said beds willnow move rearwardly preparatory to a second in the direction of tharrows,

an eccentric shaft engaging the ear apertures of at least one of thejaws, and vertical guide means connecting the jaws.

2. A machine for feeding and folding the edges f sheet metal, a pair ofsuperimposed elongated jaws, apertured ears extending therefrom, acomplementary series of equi-distant spaced die units of difierentcharacter extending from each jaw, an eccentric shaft engaging the earapertures of at least one of the jaws, and guide pins extending from onejaw in slidable engagement with the companion jaw.

HAROLD V. DETTMAN.

